Process of and apparatus for refining oils



Jan. 4 1927.

C. W. STRATF ORD PROCESS OF AND APPARATUS FOR REFINING OILS F iled Sept. 8, 1925 2 Sheets-Sheet Jan. 1927.

c. w. STRATFORD PROCESS OF AND APPARATUS FOR REFINING OILS Filed Sept. 8. 1925 2 Sheets-Sheet currentspreading theoil into a'rapidlymot'p. ing liquid sheet in i contact witlr the nner still surface and the secondary current stir-1 Patented Jan. '4, v1927.

PATENT OFFICE.

CHARLES WALCOT'I STRATFORID, OF SAN FRANCISCO, CALIFORNIA.

- I PROCESS OF AND APPARATUS FOR REFINING OILS.

Application filed September 8, 1925.

The hereinafter described invention relates to the refining of liquid hydrocarbons, although its principles and benefits may be very advantageously applied in handling other liquid substances in effecting their heating and vaporization. Insomuch as my invention has particularly amongst its pur poses the handling of liquid hydrocarbons, I will illustrate and describe its embodiment in the well known type of cylindrical oil still now generally in use in oil refineries.

Among the objects of my invention are, keeping the inner cylindrical surface of the still free from carbon deposition by causing the liquid hydrocarbon to move rapidly and continuously over the heated surface of the still, increasing the rate of firing 'of the still by protecting its bottom as exposed to hot furnace gases with a constantly moving liquid mass, increasing the rate of evaporation of the liquid hydrocarbon per square foot of heating surface exposed, eliminating all scraping devices now used within stills to eriodically remove carbon deposition, as wel as devices for collecting carbon therein. The accomplishment of these objects enables me to materially increase the capacity or output of the still while preserving the integrity of its metallic surfaces against overheating, effecting economies not now 010-- tainable in refining oil as charged in volume in a still of this type.

My process is distinguished by the fact that I cause a continuous circulation or stirring of the mass or total volume of oil in the still while forcing it to travel at high velocity over the inner heated surface of the still in a rapidly moving sheet while stilling.

This I do by discharging theoil within the still under pressure and with velocity through nozzles against its inner cylindrical surface, a dual movement of the oil in well defined circuits taking place. These two movements of the oil I will term and describe as primary and secondary currents or movements, and I desire it to be understood, that the stirring or circulation of the oil in mass and its rapid travel in contactwith the inner heated surface of the still is en tirely the result-of the forceofits'discharge against the still surface without-the aid I of mechanical I mining I devices; the'prima'ry ring it in the mass over said surface. The

Serial No. 54,947.

In order that a comprehensive understand ing may be had through the illustrative embodiment of my invention herein set out, reference should be made to the accompanying drawings in which Fig. 1 is a longitudinal section of a cylindrical oil still with heating furnace of the type now generally employed in refining oil. The still is shown fitted with the apparatus of my invention,

I which involves in the present setting a centrifugal pump mounted within the still with suction and discharge pipes. The suction of the. pump is set to draw the oil from near its bottom and to create a partial vacuum below the surface of the oil level while the discharge of the pump is connected to a pipe manifold with nozzle outlets directed to discharge the oil over and against the bottom of the still. i

Fig. 2 is a section takenon line 2-2, Fig. 1, to show the oil discharge manifold and its nozzles and the relation of the nozzles to the inner cylindrical surface of the still.-

Fig. 3 is an enlarged sectional view of one of the nozzles in the manifold showing its discharge opening adjacent the inner Sill. face of the still bottom.

Fig. 4 is a diagrammatical view showing generally how the dual; movement of the oiliis eflfected within the, still-by my process. Theprlmary movement of the oil along the inner surface of the cylindricaljsti ll athi'gh velocity is denoted by tli'e'full lin e arrows A, while the secondary movement of v the oil within the mass is denotedbylithe dotted-line ed by the line XY. i I

arrows B. The oil level in tl' estill' is, d enotl'lhe Qresulti of thi .t b'ftia' 'za i liawtiatifi is J ;..rapid;heatrexchan' e bottom and ,highwliate c In th'sjmannerI also overcome allf'un desirable localized over heating of the oil through the still aponi-z-ation at the which now takes place in stills which .are charged with oil in volume and which is the cause of carbon deposition therein.

In the drawings numeral 10 designatesa standard type of enclosed cylindrical con tainer providing an oil still. The still 10 is set over a refractory lined furnace and receives heat against its bottom in the present instance from the hot products of combustion of an oil fire, although heat from any source may be employed so long as the temperature is sufficient to eflect the vaporization of the liquid hydrocarbon in the still. Thestill 10 is provided with an oil filling inlet 11 and valve therefor 12 and a residuum outlet 13 and valve therefor 14:. The top of the still 10 has a dome 15 providing an outlet for withdrawing the vapors liberated during the stilling operation. Mounted within the still 10 is pump 16 and mounted on the exterior of the still is electric motor 17 Suitable shaft transmission means connects the pump 16 and the motor 17 through the land and stuifing box 18, The pump 16 is tted with the suction p1pe19 and the discharge pipemanifold 20. The

discharge manifold 20 comprises an assembly of pipes connected to the discharge side of the pum 16 with headers 21 running laterally of t e still 10 and connecting pipes 22 running longitudinally thereof. The headers 21 are so set with reference to the inner surface of the still bottom as to bring the longitudinal pipes 22 into close proximity thereto. Inserted or fitted into the pi es-22 atsuitably spaced intervals are nozz cs 23. The nozzles 23 provide a means so that oil pumped through the manifold 20 will be discharged against the inner surface of the still 10 with velocity. The number of nozzles employed is governed by the area of the surface over which the oil is desired to be put in motion and the intensity of the liquid movement desired to be effected.

Again, the rapidly moving liquid over. the heated surface being the result of the partial vacuum created by the pump and spread of the oil around the outlets of the nozzles, it is obvious that with a given oil discharge pressure the spacing of the nozzles over the. surface will govern the continuity of the rapidly moving liquid sheet covering formed over the surface.

It is desired to note that an equivalent form of oil discharge manifold located with nozzles adjacent the inner surface of the still against which it is desired to force the oil therethrough may be used.

In operation the still 10 is first filled with oil through the valve 12 and inlet 11 to a level XY, suitable for stilling, the volume of oil in the still being kept up to such level as desired to suit the stilling -o eration by regulation of the valve 12, w ile the residuum outlet from the still 10 is controlled by regulation of the valve 14. Upon starting the motor 17 driving the pump 16 the oil is drawn from the bottom of the still by the pump, thus creatin a vacuum below the level of the oil an the oil is forced through the discharge manifold 20 and the nozzles 23 against the inner heated surfaceof the still bottom 10 thereby effecting the continuous liquid movement of my process.

The embodiment of my invention herein illustrateed and dscribed is for the purpose of setting forth its principles and advantages and my invention is by no means limited to this showing.

What I claim is 1. The process of refining oil in a still containing a maintained quantity of oil during the stilling operation, which consists in drawing the oil from adjacent the bottom thereof to create a partial vacuum below the oil level, discharging the drawn oil under pressure in a plurality of separated streams against the inner heated surface of the still with such force and in such predetermined relation to each other as to cause each of said streams aided by said partial vacuum to form thin laterally extending, rapidly moving films of oil against the heated still surface and the several films so formed to mutually co-act to induce a rapid circulation of the oil upwardly from said heated surface to the top of the oil body and downwardly to points adjacent the heated still surface, whereby to induce a rapid circulation ofthe entire body of oil within the still and to cause its repeated contact with the more highly heated portions thereof.

2. The process of refining oil in a still containing a maintained quantity of oil during the stilling operation, which consists in continuously drawing the oil from adjacent the heating surface of the still and thereby creating a partial vacuum below the oil level, in discharging the drawn oil in a lurality of separated streams aided by said partial vacuum against said surface under such pressure and in such predetermined relation to each other as to cause each of said streams to form a thin laterally extending, rapidly moving film of oil against the heated still surface and the several films so formed to mutually coact to induce a rapid circulation of oil upwardly from said heated surface toward the top of the oil body and downwardly to points adjacent the heated still surface, whereby toinduce a rapid circulation of the entire body of oil within the still and to cause its repeated contact with the more highly heated portions thereof.

3. Apparatus for refining oil comprising a still to contain a maintained quantit of oil during stilling, means to draw oil om adjacent the heated surface of the still and create a partial vacuum below the level of the oil, and means through which the oil is discharged by said first mentioned means in a plurality of separated streams against the said heated surface with such force and in such predetermined relation to each other as to cause each of said streams aided by said partial vacuum to form a thin laterally extending, rapidly moving film of oil for the purpose specified.

4. Apparatus for refining oil comprising a still to contain a maintamed quantity of oil during stilling, means to draw oil from adjacent the heated surface of the still and create a partial vacuum below the level of the oil, pipes, headers connecting the pipes, said pipes and headers being in communication with the first mentioned means and having outlets through which the oil is discharged by said first mentioned means in a plurality of separated streams against the said heated surface with such force and in such predetermined relation to each other as to cause each of said streams aided by said create a partial vacuum to form a thin laterally extending, rapidly moving film of oil for the purpose specified.

5. Apparatus for refining oil comprising a still to contain a maintained quantity of oil during stilling, a pump to draw oil from ad jacent the heated surface of the still and partial vacuum below the level of the oil, pipes, headers connecting the pipes, a manifold in communication with the headers and with the pump, the inlet of said pump being below said manifold, said pipes and headers being in communication with the pump and having outlets through which the oil is discharged by said pump in a plurality of separated streams against the said heated surface with such force and in such predetermined relation to each other as to cause each of said streams aided by said partial vacuum to form a thin, laterally extending, rapidlymoving film of oil for the purpose specified.

CHARLES 'WALCOTT STRATFORD. 

